1. Field of the Invention
The invention relates generally to devices and methods for operation of downhole valves. In particular aspects, the invention relates to the control of valves used in wellbore intervention technology.
2. Description of the Related Art
Following a primary production period for a wellbore, wellbore intervention is often needed to pump fluids, chemicals, etc. or transport tools into and out of the wellbore. Deviated or horizontal wellbores or wellbore portions can preclude the use of wireline intervention. Where tubulars, and particularly coiled tubing, are used to facilitate such interventions, the string will typically require one or more internal safety valves such as flapper-type or check-type valves. These safety valves prevent the flow of wellbore hydrocarbons into the coiled tubing but also may limit some preferable intervention operations.